For the first time, scientists receive mysteriously delayed signals from two supermassive black holes that eat stars near them.
In the first case, a black hole weighing up to 30 million suns, located in a galaxy about 750 million light-years away, swallowed a star that passed too close to its edge. The light from the event was spotted in April 2019, but six months later a telescope in Antarctica captures an extremely energetic and ghostly particle – a neutrino – this was obviously distorted during the holiday.
A second incident involved a supermassive black hole about 1
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Both events include what is known as the Tide Event (TDE), where a supermassive black hole shatters a star into pieces using its colossal gravitational pull – essentially an extreme version of how the Moon’s gravitational pull increases the tides. The Earth. Such cosmic events are not yet well understood, and these two new discoveries should significantly help astronomers unlock their inner workings.
“Every time we find a new TDE, there can always be something exciting and unexpected about it,” said Jane Dai, who studies high-energy astrophysics at the University of Hong Kong, to Live Science. “So there are a lot of new physics that can be made,” added Dai, who is not involved in any of the discoveries.
Researchers classify tidal events as “transient” because they usually erupt over several days and then darken again. What exactly creates the light in such cases is still not entirely clear, said Asaf Horesh, an astronomer at the Hebrew University of Jerusalem in Israel and co-author of two articles on the new events, to Live Science.
As the supermassive black hole tears its star dish, the star “spaghettiizes” in a long, thin stream. This torrent of material wraps around the black hole and is thought to produce a jet of energy as it circulates like water flowing down the drain, although other models predict that some of the former star may explode outside and interact with surrounding gases. dust, generating the eruption, Horesh said.
Given the extreme environment surrounding the black hole, particles can become significantly accelerated in processes similar to nuclear destroyers such as the Large Hadron Collider in Geneva, Switzerland. Neutrinos are small specks, approximately 500,000 times lighter than an electron, and because they are neutral (without charge), they do not interact with much as they fly through space.
This allowed a neutrino to travel out of the first TDE and head for Earth, eventually appearing in a square-kilometer instrument known as the IceCube Neutrino Observatory, buried in Antarctic ice. Researchers have identified the discovery of IC191001A and calculated that it has nearly 1 quadrillion electrovolts of energy, making it one of the most powerful neutrinos IceCube has ever seen, according to a new article.s, which was published on February 22 in the magazine Natural astronomy.
While physicists have predicted that neutrinos are produced in tidal and destructive events, astronomers have never tied a neutrino back to a particular TDE, making it spectacular first. As for why he arrived six months after the event, “I have no idea,” Horesh said.
A similar mystery surrounds the second study he led, also in Natural astronomy . In this case, it could be seen that the optical light – as our eyes see it – erupts from a light snacking black hole and then disappears, as usual for these phenomena.
Horesh and his co-authors decided to conduct further research using the Karl Jansky Very Large Array (VLA) telescope in New Mexico, which detects radio waves. For months they saw nothing coming from the black hole, and then suddenly, six months after the initial event, a bright radio burst. Even stranger, VLA data collected almost four years later showed another curious burst of radio power.
“Someone can make up a story about why we saw something six months later,” Horesh said. “There’s nothing to explain why it has to ignite, disintegrate and then flare up again. It’s really interesting.”
He points to the need for new models that can explain these delayed signals. His team speculates that part of the energy jet comes out at a strange angle, producing a flaming pattern that is sometimes visible and sometimes not rotating. Another possibility is that stellar debris drives shock waves that move slowly through the material surrounding the black hole, producing energy emissions at later times, although no one really knows.
But given that these incidents are now lasting longer than originally thought, Horesh is looking forward to discovering more tidal disturbances that could give an idea of their nature.
Dai is also excited about the prospect of finding ways to study the mysteries of TDE. “These events are ideal laboratories to learn about black holes,” she said, giving researchers important clues as to how the material accumulates around them and produces jets and rockets.
The Vera C. Rubin Observatory in Chile, which is expected to start collecting data this year, could theoretically see hundreds of new TDEs, she added; and other upcoming space instruments from Europe and China should add to this award.
“The future of the field is very bright,” she said.
Originally published in Live Science.